In general, rotary power tools are light-weight, handheld power tools capable of being equipped with a variety of accessory tools and attachments, such as cutting blades, sanding discs, grinding tools, and many others. These types of tools typically include a generally cylindrically-shaped main body that serves as an enclosure for an electric motor as well as a hand grip for the tool. The electric motor drives an output shaft to rotate at high speeds. The output shaft is equipped with an accessory attachment system that enables accessory tools to be releasably secured to the power tool.
Small rotary power tools can be used to perform many tasks, some of which may be at locations in which the ambient light is relatively low. One solution to this problem is to position a light at the nose end of the power tool. While many types of light producing devices can be used, solid-state light emitting diodes (LEDs) are preferred because they are not prone to being easily damaged and emit sufficient amounts of light to illuminate the work area without requiring a significant amount of power.
In some conventional rotary power tools, the light is directly connected to the tool power source via a wired connection within the power tool. For example, for battery powered rotary tools, the light is connected to the battery by a wired connection, while for A/C powered rotary tools, the light is connected to the mains power source via a wired connection within the tool. One problem with connecting the light source to the tool power source is that the wires result in the grip profile of the tool being enlarged at the portion through which the wires are run. This can result in reduced user comfort and may be less aesthetically pleasing.
In some other conventional rotary power tools, the lights are powered by means of an onboard generating system, which can include a magnet located on the output shaft or other rotating portion of the tool. The magnet produces a magnetic field as the tool is operated to rotate, and an inductive coil on the light or inductor generates a current that is used to illuminate the light.
Another solution to lighting the power tool is to provide a long pivotable or flexible arm having a one end attached to the power tool and the opposite end including a light. The long pivot or flexible arms, however, are cumbersome and can interfere with a user's ability to see the working area or to grip the tool.
It would therefore be desirable to provide a lighting system for a rotary tool that is compact, simple to manufacture, and does not interfere with the operator's use of the rotary tool.